Railway signal system.



R. B. BRYANT.

RAILWAY SIGNAL SYSTEM.

APPLIOATION FILED NOV. 20, 1908.

Patented Mar. 9, 1915.

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ROY B. BRYANT, 0F LITTLE ROCK, ARKANSAS.

RAILWAY SIGNAL SYSTEM.

Specification of Letters Patent.

Patented Mar. 9, 1 915.

Application filed November 20, 1908. Serial No. 463,505.

To all whom it mail concern Be it known that I, ROY B. BRYANT, a citizen of the United States, residing at Little Rock, in the county of Pulaski and State of Arkansas, have invented certain new and useful Improvements in Railway Signal Systems, of which the following is a full, clear, and exact description.

This invention relates to railway signal system, particularly for trolley and like roads where cars pass through a single track section or block from both directions and in which the trafiic should be so controlled that two cars are not allowed to simultaneously enter the block from opposite ends. With installations of this character it is, however, desirable to have provision for a plurality of cars to enter the block in one direction or the other.

In carrying out my'invention I aim to do away with all step by step ratchet operated devices and other intricate mechanism, and employ merely a pair of relays at the respective ends of the block with armatures which are acted upon mechanically as well as magnetically and having contacts which complete all the functions of the apparatus.

In accordance with my invention, danger and safety semaphore signals together with lamps are provided at the respective entrances to the block and which are controlled to give proper indications under all circumstances, as will later more fully apear.

With the various foregoing and other objects in view, my invention consists of the features of construction and combination as hereinafter set forth and claimed.

In the drawings: Figure 1 1s a generally diagrammatic view showing a signal system embodying the principles of my invention. Fig. 2 is a sectional view of a practical form of trolley switch for the same.

In carrying out my invention, I make use of a continuous trolley wire which is not broken or interruped at any point, and I employ branch circuits or connections which are opened or interrupted when the block is idle, so as not use up current or endanger burn-outs. Then a car enters the block, however, a light operating current is diverted from the trolley wire, and is led through specially constructed relay magnets, each of which has separate attracting and holding functions. The operation of these relays is suchv that when a car enters the block, a clear signal is immediately exhiblted at the entering end and a danger signal at the remote end. The car about to enter from the opposite end will therefore be held up by the danger signal. If the car disobeys, it is evident that the signal should still be perpetuated in order that no controversy may arise, as to which car had the right of way in the block. In other words, a. car that wrongly and disobediently passes a danger signal, should not be able by this fact, to cause any change in the established signals, but should be compelled to back out of the block without finding any ground for controversy as to who had the right of way. It 1s, of course, within the capabilities of my invention, for two or any number of cars, to enter the single track section in succession past the clear signal displayed at the entering end, and as such cars run along close together no confusion will be caused by the fact that the first emerging car clears the red signal.

Referring to the drawings, in which like parts are designated by the same reference sign, 1 designates a trolley Wire, and 2 and 2 designate signal installments at the respective ends of a single track section or block. Each signal installment may include a white or clear signal lamp 3, and a red or danger signal lamp 4. In addition to the signal lamps 3 and 4, any suitable or desired semaphore signals 3 and 4 may be employed to move appropriately colored targets 5 into positions to give indications corresponding to the lamps.

6 and 6 denote magnets which form part of a trolley switch apparatus at the respective ends of the block. Each of these magnets acts upon an armature 7, which is movable into two positions in either of which it is adapted to be retained by the attraction of the magnet. The normal position of the armature is half-waybetween its extreme positions mentioned, and from its mean po sition the armature is adapted to be either attracted or mechanically displaced respectively to its two extreme positions. Any construction of magnet and armature may be adapted to accomplish the foregoing function, but I prefer a simple bar magnet with two poles 8 and 9, and an armature formed of a bent iron lever fulcrumed at a point 10, which islocated nearer the pole 9 than the pole 8. This arrangement causes the lever to be unbalanced and move to a certain position (as illustrated) by gravity, and also causes the lever to be tilted against the pole 8, rather than the pole9, when the magnet is energized while the lever is in the mean position shown. If, however, the lever is initially tilted into contact with the pole 9',"a nd-'the magnet then energized, the lever will be retained in this position. Also acting on the armature 7 at the respective stations are tappets 12 and 12 fulcrumed at 13 and having a springy arm 12, adapted to impinge against the short arm of the lever 7. Each tappet also has a part 12 which depends to'a point directly above the trolley wire 1, and is adapted to be engaged by the trolley wheel of a car in passing.

l4 and 15 denote fixed contacts selectively engaged by the spring blade 16, whose position is determined by the long arm of the lever 7. Contact is normally made at 14, but is interrupted and established at 15, whe'nthe armature 7 is tilted to engage the pole9, by the engagement of the tappet 12. 18 designates another spring blade normally engaging the fixed contact 19-, but depressed to break'the circuit when engaged by the tappet 12 in a movement the reverse of that which displaces the armature 7. The magnets6 -and 6 are included in a single series circuit Z between the spring blades 16 at the respective ends of the block. The blades 15 have connections 0 extending through the signals 3, 3 to the trolley wire 1, while blades 18 have similar connection 39 extending to ground through the signal devices 4, 4E": The contacts 14 and 19 are simply joined together by a wire connection 9. r

The use and'operation is as follows: Assuming that a car is passing in the direction of the arrow, and is entering the single tracksection or block which is protected by the signals, it is evident that its movement will-"canse the trolley wheel to engage the depending arm 12 of the tappet 12 and swing the latter so as to tilt the armature 7 into'contact with the pole 9 of the magnet 6 This movement of the armature also depresses the spring blade 16 into engagement with the contact 15, and a current flows from the trolley wire 1 through wire 0, signals 3,3, contact 15 blade 16, wire 1 including magnets 6 and 6', blade 16 at stationQ, wire 9, contact 19, blade 18 and wire p, including danger signals 4 and 4 to ground. This circuit includes the clear signal atthe "enteringend of the block and the danger signal at the remote end, as is desiredandthe 'energization of the magnets 6 and'6 effects the continuance of this condition as follows: The armature 7 at station 2 is maintained in its tilted position against the pole 9by' the magnetic attraction, maintaining the spring blade 16 depressed and the circuit closed at 15. Theother armature 7 at station 2 is attracted into contact with cient force to tilt the armature out of engagement with the pole 8 against which it is held by the magnetic attraction, so that this engagement continues, and the clear and danger signals already set are perpetuated, notwithstanding the entrance of a car from the right hand end of the block. Such car which disobediently'passed a red signal is thereby clearly shown to be in error and required to back out of the block to give the right of way'to those cars entering from the left hand end. When, however, the car entering from the left hand end, emerges at the right hand end of the block, it engages the depending arm of the tappet 12 in such a direction as to depress the spring blade 12 and the latter engages and depresses the blade 18, breaking the contact at 19. Inas 'much as this contact was included in the signal circuit already described, it is evident that such circuit is broken and all the signals cleared and-returned to normal position-as shown in the drawings. 'It is evident that the armatures 7 move in this way"- to their normal positions whenthe magnets 6* and 6" are deenergized, under the influenceof gravity, due to the prepondering weight of their long arms.

It will be noted that the apparatus at both ends of the block section is exactly similar or symmetrical so that the action is enactly the same for cars entering in both directions, and all the foregoing functions which have'been considered for cars entering in certain-conditions or directions will take place in exactly the same way for the reverse conditions or directions.

By the foregoing mechanism it will be seen that I have accomplished all the functions set forth in the preliminary part of this specification. The apparatus'prote'cts a single track block section, operating equally and similarly for cars proceeding in one direction or the other. No current is tus; the trolley wire is unbroken and alight operating current is drawn therefrom in a single series circuit toset the various signals while the block is occupied. No unusual or wrongful acts on the part of the motorman of the cars can so'di sturb the action of the apparatus as to produce any controversy, and the discipline is" therefore made certain wasted during idle periods of the appara- V and inforceable. Inasmuch as all the signals and magnets are in a single series circuit, any break or failure to act in any part is accompanied by corresponding conditions throughout, and the fact of the failure is speedily noted and communicated to the proper authorities. The entire apparatus, except the signals, is capable of being housed in a compact trolley switch as shown in Fig. 2, having a protecting hood 25 to protect the parts from dust and adverse weather conditions, and a depending guide 26 which keeps the trolley wheel against dislodgment from the trolley wire while it is passing and operating the tappet 12. The switch may, of course, be supported by guy wires and take the place of any ordinary hanger along the line.

What I claim, is

1. In a signal system for single track trolley roads, a block having a normally open circuit, clear and danger signals, contacts for selectively including said signals in said circuit, armatures operated mechanically by the passage of a car for operating said contacts, a magnet at each end of the block and included in said circuit for retaining said armatures in displaced relations, the magnet at the opposite end of the block from the entering end retaining the armature with sufficient force to prevent any change in the signals when the car enters an occupied block from said opposite end of the block.

, 2. In a signal system, a tappet at one end of a block adapted to be displaced by the passage of a car, a magnet having its armature moved by the tappet, a signaling circuit closed on movement of said armature by a car entering the block, a magnet and armature at the opposite end of said block, said signaling circuit including both magnets, a tappet, a spring thereon, the armature at the opposite end being in the path of said spring but being held with sufficient force by said magnet when energized to prevent the spring from actuating said armature, whereby a car entering from the opposite end is prevented from actuating the armature at that end when the signal circuit is closed.

3. In a signaling system, a line wire extending between two stations and connected at each station with two branches, a normally closed switch at each station connecting one branch with one pole of a source of energy, a normally open switch at each station connecting the other branch with the other pole of the source of energy, a magnet at each station in the line conductor, an armature for each magnet pivoted between its ends so that one end is acted on by one pole of the magnet and the other end by the other pole, said ends being normally held at different distances from their respective poles, a tappet at each end of the block in the path of a moving vehicle, each tappet when moved by a car entering the block being adapted to displace its armature and thereby close the normally open switch, and adapted, when moved by a car departing from the block, to open the normally closed switch, whereby a car entering the block will close the circuit through both magnets, the magnet at the entering end holding its armature displaced to hold the circuit closed, and the magnet at the opposite end holding its armature to prevent displacement thereof by a car entering the block from that end.

In a signal system, magnets having armatures mechanically displaced by the passage of a trolley wheel, means actuated by a mechanically displaced armature for energizing said magnets to attract the other armature and hold the mechanically dis-- placed armature in its displaced relation, danger and clear signals at each entrance to a block, and means actuated by the movements of said armatures for selectively exhibiting the signals at the respective ends of the block.

5. In a signal system, magnets having armatures mechanically displaced by the passage of a trolley wheel, clear signals having a circuit adapted to be closed by such displacement when a car enters the block, said circuit energizing both magnets whereby the mechanically displaced armature is retained, and the other armature is magnetically displaced to: the alternate position, and a danger signal at the remote end of the block normally included in said circuit.

6. In a signal system, magnets, tiltable armatures therefor, mechanically displaced by the passage of a trolley wheel, a circuit including said magnets closed by the tilting of either armature in one direction only, whereby the mechanically displaced armature may be retained and the other armature attracted to its alternate position, said last named armature being retained in such attracted position notwithstanding the passage of another trolley wheel which enters the block at the opposite end.

7. In a signal system, magnets having armatures mechanically displaced by the passage of a trolley wheel, a circuit closed to energize said magnets when a car enters the block, whereby the mechanically displaced armature is retained and the other armature attracted to an alternate position, and means for interrupting said current when the car leaves the block.

8. In a signal system, a trolley line, a branch thereof normally open, a trolley wheel, a magnet in said branch, an armature, a pivot for said armature and located between the ends thereof, the armature being normally held so that one end is nearer the magnet than the other, a tappet in the path of the trolley Wheel, a spring attached to said tappet, and adapted to displace said armature When the tappet is actuated, means for closing said normally open branch, the magnet when energized holding the nearer end of the armature so powerfully that said spring yields and fails to move said armature When the trolley Wheel actuates said tappet.

9. A device of the kind described comprising a line Wire, tWo circuits in which said line Wire is included, two magnets located adjacent the opposite ends of said line Wire, an armature disposed contiguous to each magnet, each of said armatures being fulcruined eccentrically between the-poles of its magnet, a signal disposed at each end of said circuits, a fixed and a movable contact disposed in spaced relation associated With each of said circuits, the long arm of each of said arniatures being engaged normally With the movable contact, and means for mechanically actuating said armatures to cause either of said arinatures to actuate the movable contact to close their respective circuits.

In Witness whereof, I subscribe my signature, in the presence of tWo Witnesses.

,n ROY B. BRYANT.

lVitnesses T. CENoUsE, HoUs'roN GRON.

Copies of this patent may beobtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

